Power line arcing

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Fulthrotl said:
well, it's a jacobs ladder, and most of the heat is being generated off
of the wire, in the plasma, so they will last a while..... the arc tips on HV switches
last a pretty long time, don't they?
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Slapping phases together damages the wire. No way around it. The wire is not made to be an arc tip.
 
The lines dont have to touch for those arcs to form. So a few trillion atoms get fried off each arc... remember, avogadro's number has a 23 exponent... can pull lots and lots of trillions from that and never touch it. Sure the conductors will eventually burn out or break but I'd bet the process takes a fairly long time. Cool video and gif, and Ive never seen intersecting powerlines like that either... obviously too close for the wind load harmonics.
 
Looks to me like some were physically slapping together. Some additional arcs created using established arcs.
 
JFletcher said:
The lines dont have to touch for those arcs to form. So a few trillion atoms get fried off each arc... remember, avogadro's number has a 23 exponent... can pull lots and lots of trillions from that and never touch it. Sure the conductors will eventually burn out or break but I'd bet the process takes a fairly long time. Cool video and gif, and Ive never seen intersecting powerlines like that either... obviously too close for the wind load harmonics.
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More likely a magnetic "motorizing effect". Notice that the wires spanning the other poles are not moving at all. Short circuits and the associated torque can do real damage. Find out who the engineer was and FIRE HIM! Or maybe give him a medal for producing lineman overtime!
 
JFletcher said:
obviously too close for the wind load harmonics.
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Looking at the video again, the trees are not moving. This is a case of pure conductor slapping. A high fault (or alternately line contact like a car hitting pole or object falling on line starting the motion) occurred and pushed the conductors apart. When the fault cleared, the conductors slapped together. With the close-space construction and long span, this set up and oscillation of faults and pulling forces. They need to install insulating spacers in the long spans there.
 
meternerd said:
More likely a magnetic "motorizing effect". Notice that the wires spanning the other poles are not moving at all. Short circuits and the associated torque can do real damage. Find out who the engineer was and FIRE HIM! Or maybe give him a medal for producing lineman overtime!
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Motoring is the term used to describe the arc traveling. This helps move the heat down the line and avoids damage. When the arc reaches a slow-down point (insulator tie, covering, certain splices, etc. the line can be damaged). Continued arcing can also cause damage (worse with smaller conductor).

The effect seen here is called slapping.
 
Trees not moving - the evergreen trees are not all that big, the other trees have no leaves.

Other lines not moving - most of them are perpendicular to the ones that are moving and probably parallel to the wind. The fact the perpendicular run is attached to same pole probably helps add some stabilizing effect to that pole.
 
kwired said:
Trees not moving - the evergreen trees are not all that big, the other trees have no leaves.

Other lines not moving - most of them are perpendicular to the ones that are moving and probably parallel to the wind. The fact the perpendicular run is attached to same pole probably helps add some stabilizing effect to that pole.
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I'm still leaning toward wind myself. I looked up "powerline slap" and got "conductor gallop", which is caused by wind. There are several videos of this on youtube, which share something else in common with the gif and video Rick posted: snow on the ground... and likely ice on the lines, which can form unevenly causing the line to act like an airfoil, making it more susceptible to winds.
 
JFletcher said:
I'm still leaning toward wind myself. I looked up "powerline slap" and got "conductor gallop", which is caused by wind. There are several videos of this on youtube, which share something else in common with the gif and video Rick posted: snow on the ground... and likely ice on the lines, which can form unevenly causing the line to act like an airfoil, making it more susceptible to winds.
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Could be the wind causing the conductor slap. You can see the tree on the left moving slightly in the wind.

What is hard to tell is what is arcing to what each time. The angle and crossing lines plus the video speed all make it hard to see.
 
JFletcher said:
I'm still leaning toward wind myself. I looked up "powerline slap" and got "conductor gallop", which is caused by wind. There are several videos of this on youtube, which share something else in common with the gif and video Rick posted: snow on the ground... and likely ice on the lines, which can form unevenly causing the line to act like an airfoil, making it more susceptible to winds.
Click to expand...

A couple months ago the lines near me were really whipping around, the wind wasn't all that strong but this is out in the open country. Near my house is better sheltered and trees were hardly moving, but cross wind in open area plus a little ice build up on the lines gave them enough surface area to be pushed easier by the wind. The lines in the better sheltered area were still whipping around from the motion energy transferred from further down the line.
 
A couple years ago, the lines across the street from me were 'galloping'. I have some videos. There was NO wind. The lines were galloping along one road for several miles, the most pronounced being across the street from my house. It was really strange! It went on for hours, then faded away.

Jokingly, a friend of mine and I said something to the effect of, 'I wonder if this means there is going to be an earthquake?'

The next day there was one, in Guatemala IIRC.
 
mivey said:
Looking at the video again, the trees are not moving. This is a case of pure conductor slapping. A high fault (or alternately line contact like a car hitting pole or object falling on line starting the motion) occurred and pushed the conductors apart. When the fault cleared, the conductors slapped together. With the close-space construction and long span, this set up and oscillation of faults and pulling forces. They need to install insulating spacers in the long spans there.
Click to expand...

Either that double the voltage so one circuit can be eliminated. There is a video is LV conductors in NY doing the same, just have to find it...
 
mbrooke said:
Either that double the voltage so one circuit can be eliminated. There is a video is LV conductors in NY doing the same, just have to find it...
Click to expand...
That was a crowded crossing. I have dropped UG to help with crossings before.
 
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